1. Field of the Invention
The present invention relates to a rolling element accommodating tool.
2. Description of the Related Art
In a linear motion device comprising a rail and a block that moves linearly relative to the rail, and provided with an endless circulation path through which a rolling element (a ball) circulates, the block is moved relative to the rail via a plurality of rolling elements circulating through the endless circulation path while rolling.
In such a linear motion device, adjacent rolling elements chafe against each other along with the movement of the block, inhibiting smooth rolling and causing noise. Rolling element accommodating belts have therefore been used in conventional practice to align the rolling elements in the direction of arrangement within the endless circulation path.
Various rolling element accommodating belts of such description have been proposed; for example, there are those containing a reinforcing material to improve tension strength (see Japanese Laid-open Patent Application No. 2001-74048).
When a filler (comprising short fibers) is admixed as the reinforcing material, belt wear causes the filler to leak out, and it is possible that the longevity of the linear motion device could be compromised.
When long fibers such as carbon or glass are embedded, there are no such problems with leaking, but effective reinforcing is not accomplished and sufficient tension strength is not yet achieved.
Specifically, when conventional long fibers are used as a reinforcing material, the binding force between the long fibers and the resin (base material) depends on the adhesive force at the interface between the long fibers and the resin. Therefore, there have been problems with the resin peeling away from the long fibers before the long fibers exhibit their tension strength when tension is applied.
In view of this, techniques have been proposed for making the cross-sectional shape of the long fibers polygonal, for example, to increase the contact surface area between the long fibers and the resin, but there is no difference in the sense that the cross-sectional area virtually does not change in the longitudinal direction and the binding force remains dependent on the adhesive force of the interface between the long fibers and the resin, and the fact is that the problems described above have not been resolved.
When long fibers of great tension strength are used, another problem encountered is that excessive bending strength affects the smoothness of the linear guiding motion.